Design and Implementation of Intelligent On-Site Error Calibration System for Potential Transformers in GIS
XU Min-ru · Electrical Measurement & Instrumentation · 2014
When on-site error calibration is conducted for potential transformers in GIS, due to the uncertainty of distributed capacitance, conventional test methods have the problems of boost difficulty and operation complexity. Based on the technology of inductance modulation after frequency modulation(FM)and years of on-site operation experience, this paper designs and implements intelligent on-site error calibration system for potential transformers in GIS. The composition and implementation scheme of the system is introduced, and the method of distributed capacitance calculation for tested potential transformers is proposed using low-voltage FM resonance. The structural design method of the programmable high-voltage reactor is given, and the hardware and software design methods of the intelligent inverter control power are introduced. Experiments show that the calibration system can calculate accurately the distributed capacity of the tested potential transformer, adjust automatically the programmable highvoltage reactor, realize automatically resonance boosting and error calibration, and therefore improves the technical level of on-site test and working efficiency.